The charge entering the positive terminal of an element is q = 5 sin 4 t

The charge entering the positive terminal of an element is

q = 5 sin 4 π t mC

while the voltage across the element (plus to minus) is

v = 3 cos 4 π t V

(a) Find the power delivered to the element at t = 0.3 s.
(b) Calculate the energy delivered to the element between 0 and 0.6 s.